Algae have gained significant importance in recent years given their advantage in solving several critical global issues such as the production of renewable fuels and animal feedstock, reducing global climate change via carbon dioxide remediation, wastewater treatment, and sustainability. Algae farming is also used for the production of food, feed, nutraceuticals, chemicals, biofuels, pharmaceuticals, and other products that can be extracted from algae.
Algae's superiority as a biofuel feedstock arises from a number of factors such as high per-acre productivity when compared to typical terrestrial oil crop plants, non-food based feedstock resources, and its ability to be cultivated on otherwise non-productive, non-arable land.
Several thousand species of algae have been screened and studied for lipid production worldwide over the past several decades, of which about 300 species rich in lipid production have been identified. The lipids produced by algae are similar in composition when compared to other contemporary oil sources such as oil seeds, cereals, and nuts.
As the United States has already consumed over 80% of its proven oil reserves, it currently imports more than 60% of its oil. It is anticipated that within 20 years the United States will be importing in the range of 80-90% of its oil. Much of this imported oil is supplied by nations in politically volatile regions of the world, a fact which poses a constant threat to a stable oil supply for the United States. Although the United States can continue to increasingly import foreign oil, global oil supplies are not infinite and importation continues to increase the United States trade deficit and create an increasing burden on the economy.
Commercial cultivation of lipid-producing algae provides a solution to the growing problem of oil shortages and increases in cost of importation. Algae oil can be used to replace petroleum-based products. Algae can be used to generate oil of varying lipid profiles for use in a variety of applications, including, but not limited to, the generation of diesel, gasoline, kerosene, and jet fuel.
Algae farming typically uses photobioreactors (PBRs), such as flat panel PBRs and tubular PBRs, which are small in volume in order to improve the amount of light utilized by the algae. These devices have high productivity, but not high enough to make up for the loss in volume. Other PBR systems, such as ponds, raceways or troughs are used to provide larger scale production, but these systems suffer from low productivity. Current PBR systems are typically designed with flat bottoms where solids settle out, and over time potentially lead to bacterial and fungal growth. Such unwanted growth potentially decreases the productivity and growth of algae. Additionally, pond systems are large systems (half acre, acre, or hectare size) with minimal mixing. Mixing in these systems is often accomplished by way of paddle wheels or air lines, which are not optimal for algae growth, and do not develop a systematic pattern of mixing within the system to keep solids from settling out. Optimal mixing of such systems require large amounts of energy, reducing overall cost efficiency. Pond or raceway systems also require maintenance such as draining, harvesting, and cleaning to maintain optimal productivity levels for algae growth. This results in downtime of the system, labor to clean, and large amounts of water to refill these systems.
The present disclosure provides V-shaped PBR systems designed for optimal productivity at large volumes in order to deliver a high yield per acre. These systems produces large volumes of algae in a highly productive and cost efficient manner.